EPAS1 and hepatocellular carcinoma: To evaluate the HIF-2α expression difference of hypoxia-inducible factor in hepatocellular carcinoma cells in hypoxic environment, we detected the difference in HIF-2α expression levels of hepatocellular carcinoma cells HepG2 and Huh7 in normal and hypoxic conditions by immunofluorescence first, and the results were as shown in Figure 1A, in which the expression levels of HepG2 and Huh7 HIF-2αwas significantly increased in hypoxic conditions.